The present invention relates to an electrical element such as a solid-electrolyte capacitor including a body constituting an anode and metallic end-fittings constituting output electrodes, the anode end-fitting being welded on an anode wire projecting from the said body, the anode wire and the said body being made of a metal such as tantalum having a higher melting temperature than the anode end-fitting metal which is preferably metal such as nickel or a nickel alloy.
In the known capacitors of this type, the anode end-fitting is shaped as a clevis or as a hollow capsule formed of a thin sheet whose thickness is several times smaller than the diameter of the anode wire. The latter is circular in section and is therefore in a massive or solid form.
Under such conditions, the assembling of the anode end-fitting on the anode wire by welding is very difficult to perform. Indeed, for the welding to take place, a melting of the parts to be assembled must be obtained. Now since the wire is in massive form, a considerable amount of heat is necessary to reach its melting temperature. In contrast, the thermal inertia of the end-fitting constituted by a thin sheet is relatively low.
This is the reason why the assembling of the known capacitors which has just been described is very difficult to control. There are a great risk of vapourization of the end-fitting material and a very high proportion of defective products after the welding operation. Defects such as burnings or perforations, or insufficient service life, of the end-fitting are of frequent occurrence.